1. Technical Field
This disclosure is related to generation of video images and, more particularly, to apparatuses and methods for generating picture-in-picture video images.
2. Discussion of the Related Art
In conventional picture-in-picture (PIP) systems, a first image sensor generates a first image, and a second image sensor generates a smaller and lower-resolution second image. Each of the image sensors provides video image data for its respective image in the form of a video image data stream. Typically, the data of the video image data stream for the second, smaller image are stored in a frame memory. Overlay logic receives the video image data stream from the first image sensor and the video image data stream for the second image from the frame memory and combines the two images to generate a video image data stream for the PIP image output. The PIP video image data stream output from the overlay logic is then used to generate a composite PIP video image.
The frame memory for these conventional systems is necessarily large, because it is required to store large amounts of video data. Since the frame memory takes up a large amount of space on an integrated circuit chip die, it cannot be integrated with the image sensors, and is, therefore, fabricated as a separate individual device element in a conventional PIP system, which occupies a large amount of space. Also, the separate frame memory results in relatively high overall system power consumption due to the large number of required memory access operations.